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LabVIEW vi communication with MODBUS

Yes Ofcourse. its different one. However I want to capture the data. Through NI OPC i got now. 

 

I had tried same you said, before NI OPC. and I have attached also. But i didn't get the output...

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In your Modbus command, you are only reading 1 register.

 

You need to read 2 registers so that you can get two 16 bit values and be able to join them into a 32 bit value that you can typecast to Single.

 

Also your holding register may be #40245, but that is not the value that gets passed in the communciation protocol ad not what LabVIEW wants in the Modbus command.

 

Drop the 4 at the beginning.  Subtract 1.

Make your Modbus command say Starting Address 244 and Quantity 2.

 

All you never wanted to know about Modbus.

http://www.modbus.org/tech.php

 

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